MinGW 5.11.2 install with empty dll files

[mediendynamik.de]

Hallo,

I installed qt5.11.2 from
http://download.qt.io/official_releases/qt/5.11/5.11.2/qt-opensource-windows-x86-5.11.2.exe
on two different Win7 systems, both without virus scanner, and this several times.
Choosen: MinGW53_32-binaries + MinGW/Strawberry-Installation

In any case the following dll files in the folder <qt>\5.11.2\mingw53_32\bin are present, but empty (0 bytes):
Qt5OpenGL.dll, Qt5Printsupport.dll, Qt5SQL.dll, Qt5Test.dll, Qt5Widgets.dll, Qt5Xml.dll (debug and release)
The same in some plugin folders:
qtuiotouchplugin.dll
qwindows.dll
windowsprintersupport.dll
I don't searched all...

Has anyone the same experience or a solution?
Is it a broken build Install file? (installation run through without any error!)
Is it a known issue?
Thanks for helping!

L.K.